From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BF398332EC8 for ; Tue, 16 Jun 2026 12:44:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781613866; cv=none; b=KqBG5ZDplTskLk2kDgc/SmOvLpE3gAXXd4jwaqh6bVmhOZsXUvJ7A7i2bSfraI36/et2ujy1Zlp2/8LFxgljMdI8bluyjorgmziYnvUAcvS9O/Zk/B+fP+bpvqUBuXNK8faiEobYbhk9/CFsU4CGFmHTs1doXJkb/SVRgIz6Nf0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781613866; c=relaxed/simple; bh=IcgWcPwM1KKpn5LiFW0t0RVF5ikggCRb978/0Cj7k+U=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=CWrNJB3V485ygdYBTr8PmpGAbRgSAMXdayt3PrC21fnB7AQ6a9pCRNg1qNyCbmpbbYtTS/E32twQNMRjIgcE8pEHGnBqiJArZGR+q2Wda3BBOVDWoa+WFc22Xp/j5pnSwvirQWcS4TuOKWN8rDbR04hGfyW7FIITfhNxQ0Ig+i4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=bxvBFBH0; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="bxvBFBH0" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=zTf6nO17tyPUpXJxvkfLf4T174S78jpH1u5vzkpsADo=; b=bxvBFBH0NOz8dmNOBcqw355LdE gHztkxBaxJx2zx148/nI74Qu5NFD+7tp7R7DfYoboT5ai+y6PtsTwa/Up7lgZ6n4sQQUsrcLal5ES v+T2fdmsf5wAp5r9j9EwoJnJiToyNlAk9sJdpUUV8EbF/8Kc4u5ebYVDes+D1mofEfuLVAZnmF2Oa zsXloSIwoY7nzBMGbvbmbKAiHyGWpxYhMb8suu9/uJzzSkOM5K1vq8vaL/yFj3YI+8pSzAJhVLo9J 7oMMj38aDbXs3BaUnjqkmBr6PDzovV+BGncBT2APNiHwd8YT3ZHYvFujc2XsDMc496TohFr4D1lt0 4G0zVi/w==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1wZT9N-00Dr66-0d; Tue, 16 Jun 2026 12:44:17 +0000 Date: Tue, 16 Jun 2026 05:44:12 -0700 From: Breno Leitao To: Petr Mladek Cc: Tejun Heo , Lai Jiangshan , Andrew Morton , linux-kernel@vger.kernel.org, Omar Sandoval , Song Liu , Danielle Costantino , kasan-dev@googlegroups.com, kernel-team@meta.com Subject: Re: [PATCH v2 4/5] workqueue: Show all busy workers in stall diagnostics Message-ID: References: <20260305-wqstall_start-at-v2-0-b60863ee0899@debian.org> <20260305-wqstall_start-at-v2-4-b60863ee0899@debian.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Debian-User: leitao Hello Petr, On Tue, Jun 16, 2026 at 02:38:11PM +0200, Petr Mladek wrote: > On Thu 2026-06-11 07:50:04, Breno Leitao wrote: > > > > Unfortunately I didn't get the other pr_info(), because of console settings, > > but, I can say the following from this issue and previous code: > > > > 1) in show_cpu_pool_hog, found_running variable is set to false. > > 2) hash_for_each() never found any running task > > 3) The following code was trigger and was very helpful: > > > > if (!found_running) > > trigger_single_cpu_backtrace(cpu); > > Great. So, the extra complexity was worth it. Should I clean it and > send a proper patch? Or would you like to do so? I am happy to do so. I had a chat with tejun yesterday, and I got the impression he is OK with this patch as well. > Also I wonder whether it would make sense to revert the commit > 8823eaef45da7f ("workqueue: Show all busy workers in stall > diagnostics"). This patch undo that change already. Would you like to see a full revert or, are you OK with this patch reverting that behaviour? Maybe with a fixes: tag? > If I get it correctly then printing all busy workers > was not that helpful. Namely, the sleeping workers should not prevent > progress. Ack!